Pulverized fuel burner



March `22, 1932. C'AMBERS 1,850,277

PULVERIZED FUEL BURNER Filed March 2, 1928 2 sheets-sheet 1 March 22, 1932. H, CAMBERS 1,850,277

PULVERIZED FUEL BURNER Filed March 2, 1928 2 Sheets-Sheet 2 /NV-NTOR 7 M2/WML Patented Mar. 22, .1932

UNITED STATI-isk l HARRY cAMBERs, or LONDON, ENGLAND, Assraiiro" ro iiiuiiiis'rn HoiRATio LiinLowl, )t

or MORTLAKE,- ENGLAND` y PULVERIZED FUEL BiIRNER Application filed March 2, 1928, Serial No. 258,626; and in Great Britain March 3, 1927.

This invention relates to pulverized fuel burners of the kindv embodying a plurality of spirally disposed longitudinally adjustable vanes mounted within the barrel kof the burner in the pat-h of the rmain fuel and air stream. An object of the present invention is to provide a construction of burner of this nature in which a widerange of control of the length of flame can be obtained, varying from a relatively short flame with great lateral spread suitable for short furnaces of large area, to a long more or lesscylindrical flame projected to 'a considerable distance. In order to utilize fully the centrifugal' effect of the whirling motion imparted to the miX- ture by the vanes there should be little or no constraint imposed on the whirling mixture by any surrounding portion of the barrel after the mixture has yleft the ends of the vison of a pulverized fuel burner of the kindl l above referred to wherein the range of relative adjustment of the burner barrel and the spirally disposed vanes is such that in the eXtreme forward position of the vanes their` front ends lie at or close to the outlet end of the barrel the other extremityof adjustment being substantially in rear thereof, and that portion of the barrel within the range of adjustment being substantially uniform in cross section.

Two forms of construction, by way of example,` are illustrated'in the accompanying drawings, in which Fig. l is a front elevational view of a burner having longitudinally slidable but non-rotative vanes.

Fig. 2 is a. plan view partly in section, and Fig. 3 a vertical longitudinal section of the same.

A is a burner cylinder or barrel provided with a` rear end wall B through which enters the arial inlet Ypipe @for miXedfland V- air under pressure.I .S'lidable longitudinallyv inside theylnderaf barrel. A. .iSv-a truncated conical member D carrying a number of spiral lvanes E disposed in ythe path of the mixed fuel and. air issuing. from the inlet pipe C whichpas willbe seen, ,enters the smaller end of ,the c on'e D. yThe flatter is provided with a pairof bosses F into whichare screwed rods G. which pass through the rear wall B and are pivotally .attached to. the forked endsjof .a lever H pivoted to a bracket I securedto the rear wall Surrounding the Vcylindergr barrel A. is a conicalfcasing J to Lwhiclrairrr` 'ddtnfll t0. that entering `through C x and/under pressure may be supplied throughr connectionsK r'controlled by Val-.ves Lj'the air being delivered through` the aniiularjopening M surroundingthe outletof the burner, j l The spiral-vanes E impart a rotary motion to` .thenmiXedk fuel and air, .bringing aboutv a more intimate .mixture thereof and deliver,- ing a whirling flame from the outlet of the burner.y The length of this flamey isjkconn trolled by .moving the vanes longitudinally meansof the leverH, along flamebeing producedl by'slidingthe varies rearwardly towardsftheinlet pipe ClfromA a7 position. where the discharge ends ofthe .varies substantially coincide withthe discharge. end ofthe barrel or vcylinder A to ay positionffurther back .within the barrel so that the gases Iare constrained byl thercylinder` or ybarrelA and projected more or lessaXially., A f. y Vheli, however, the vanes are moved-'forwardly toward. the mouth'or discharge end of the cylinder .or barrelAY there kis a large lateral spread of thelmaterial issuing; from the discharge; end` ofthe cylinder orjbarrel due to thecentrifugal 'effect of their whirling inotion,' and short; broad flame is produced. i

Besides the advantage of veryy complete control of the length of flame, the burner of the present invention is free from the liability of clogging or becoming obstructed by deposit of fuel, ash, or dust inside the burner,

sinceby moving the vanes quickly longitudinally back and forth a few times or by bringing the end of the coned member D sharply into contact with the rear .vall B of the burner, the obstructing material may be shaken loose and blown out of the burner.

In carrying my invention into practice it is to be understood that I may provide an alternative form of construction in 'which the vanes are fixed and the barrel or cylinder sur# rounding them axially movable, so as to ob# tain the requisite amount of relative axial movement between the van'es and thebarrel, the outlet or discharge ends of the vanes and the barrel being substantially coincident in one eXtreme position of such relative move# ment. Y

What I claim is l. A pulverized i'uel burner comprising a cylindrical barrel, a single inlet pipe for the fuel and air mixture entering axially at one end of the barrel and projecting to a certain distance therein, a truncated conicalmember having its smaller end surrounding the projecting portion of the inlet pipe and its larger end making a sliding ltit With the inside of the barrel, a plurality of spiral vanes secured to said conical member so as to be slidable Within the barrel from a position in which the front ends of said vanes substantially coincide vvith the outlet end of the barrel to c. produce a relatively short broad flame to a postion farther back in the barrel to produce a relatively longer narrower flame and means for effecting such sliding movement from outside the burner barrel. V

2. A pulverized fuel burner comprising a cylindrical barrel, a single inlet pipe for the fuel and air mixture entering axially at one end of the barrel and projecting to a certain distance therein, a truncated conical member having its smaller end surrounding the inner projecting portion of the inlet pipe and its lar-ger end making a sliding fit With the in side of the barrel, a plurality of spiral vanes secured to said conical member so as to be slidable Within the barrel 'from a position in which the front ends of said vanes substantially coincide with the outlet end of the barrel to produce a relatively short broad flame to a position farther back in the barrel to produce a relatively longer narrower flame, means for effecting such sliding movement from outside the burner barrel, and a casing surrounding the barrel to receive air under pressure and having an annular outlet surrounding the outlet end of the barrel.

HARRY CAMBERS. 

